Cho 7,8gam hỗn hợp A gồm metanol và etanol tác dụng với kali dư thu được 2,24 lít khí hidro ở đktc. Xác định thành phần phần trăm về khối lượng các chất trong hỗn hợp đầu ,tính khối lượng kali đã dùng và tính khối lượng muối thu được.

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

The best solution for preventing harm to people and pets from severe hurricanes involves determining and warning residents about what

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms